Lifter jack



Patented June 28,- 1932 l lUNITI-:DSTA'IES gFNUF-PV" OFFICE 5- MILLARD B. LUCKER, oF BENTON HARBOR, MICHIGAN, AsSIGNoR To AUTO SPECIALTIES MFG. Co., oF SAN FRANCISCO, CALIFORNIA, YA CORPORATION OF CALIFORNIA. f

LIFTER .TACK

Appncatin nieu February s, 192s. serial No. 252,089.

My invention relates in generalv to lifting jacks and has more particular reference to a als jack of the double-lift type, the main feature of which is a low initial jack height to ltake care of thelow front axle of modern low slung automobiles especially` whenthe tire is deflated, the jack having telescoping lifting elements adapted for extension through a lifting range sufficient to accommodatethe relatively high rear axles. ,f

Such a jack is illustrated and described in my pendingapplication Serial No. 242,697

filed December27, 19.27 and my presentinvention contemplates the provision of a jack wherein the double lift principle is embodied in asomewhat simpler and :more rugged mechanism thanthat illustratedl andy described in my above mentioned application.

One object of my invention is toprovide in a double-lift jack, simple means for pre-- venting the rotation of a lifting member as it is raised in the jack frame.

' Ayfurther object of my invention is the provision Ofa friction pad engaging a ,lifting member whereby relative rotation of the member may ,bejprevented as it is raised in the frame,kr but is` not suflicfiently firmly pressed upon the lifting member when the latter is rotated'by a, positive'vdriving connection.A `L d I, e

w Numerous other objects and advantages ofthe invention will be apparent as lit is better understood from the following description whichtaken in connection with the accompanying drawing discloses a preferred embodiment of the invention., Referringk to the drawing: e Figure 1 is a vertical cross-section taken through a jack embodying my present invention' l f Figure 2 is anelevation lview takenv froml the right in Figure 1 and showing the jack in partially and fully extended position; parts of jack bein shown broken away toreveal the details O construction; 1

Figure'V is a horizontal cross Ysectiontaken substantially along the line 3-,-3 in Figure 1' and Y ,Figure 4 is a horizontal crosssection'tak'en substantially along line 4 4; of'- Figure 1.

To illustrate my invention I have shown on the drawing a preferred embodiment comprising an integral retaining frame forming abase 11, a cylindrical sleeve 13 extending upwardly of the base and a bearing support 15 karranged at the top of the cylindrical sleeve. l The base sleeve and bearingsup port are formed in one piece, and Strengthen-k ing kwebs 17 are arranged at the junction of the'fparts. The'bearing support l5 extends 50 across the upper openv end of the sleeve and carries a bearing 19 aligned centrally thereover. The bearing support comprises a'strip of material extending across the upper end of v the sleeve and having downwardly extending O5" ends which are formed integral with the sleeve, being attached to opposite sides of the sleeve, one at the top and the other at av point "in the sleeve, substantially removed from the upper end of the sleeve. A bearing 31 is formed in the longitudinal end of the bearing support, that is to say, the end which is attached to the sleeve at a point substany tially below its upper end. A bevel gear 21 o having a h ub 23 is journalled in the bearing 75 19 and has'a toothed periphery 25 extending outwardly to engage a oo-operating pinion 27 carried Ona stub shaft 29 which is rotatably mounted in the bearing 31,1endwise motion of the stub shaft being prevented by a-shoulder 33 formed thereon. The stub yshaft extends through the bearing 31 'and is providedwith a socket 35 having, in the illustrated embodiment, a square cross section and adapted to accommodate the squared end of anfoperat- V ing handle (not shown) by which the rota#l tion of the pinion yand gear may be accomplished at a distance from the j ack. Y 1

The inner walls .of the sleeve l13 delinea Vcylindrical channel. 37 extending through the 90 base 11to the upper endof the sleeve which is finished to provide a bearing seat 39. The lower lend ofthe bearing 19 andthe seat 39 areV spaced apart a distance suliicient to allow'the bevelled ygear 21 tobe slid edgewise 95 beneath the bearing 19 and the gear may then be positioned by moving it upwardly, the hub 23 thereof sliding axially into place in thev bearing. The gear 21 isfsupported in'position by a roller bearing 41 which may be slid edge-A 100 formed on the tube throughout .its entire length. -The threads 51 are adapted to. co-

operate with internal threads 57 formed in the hub 23 of the gear 21, while the internally threaded portion 53 extends a short distance into the tube. rlhe shaft 45 is assembled through the lower end of the tube 49 by engaging the threads 47 and 53. After the shaft is thus assembled, the tube and shaft may be inserted in the sleeve 13 through the lower Vopen end by sliding them longitudinally through the channel 37 and through the opening 43 in the roller-bearing 41. The opening 43 and thechannel 37 being of sui?.-

- cient size to accommodate the tube freely.

The external threads may .then be mated with the internal Vthreads 57 of the gear 21. After the tube is threaded through the gear in this manner, a peg 59 is s et in the groove of the threads 51 adjacent the upper end of the tube, which peg by engaging the upper end of the gear 21y limits the downward motion of the tube through the gear 21. A siniilarpeg 55 is set in thegroove of thethreads 51 adjacent the lower end of the tube, which peg similarly limits the upward movement of the tube through the gear 21. A pin 6 1 is secured in the groove of the threads 47 adja cent the lower end of the shaft 45, which pin, by engaging the lower end of the threaded portion 53 limits the upward axial movement of the shaft through the tube. Aload-carrying head is rigidly mounted at the upper end of the shaft 45, and the axialV downward movement of the shaft through thetube 49 is vprevented by a shoulder formed onthis head. Y d d Y d Upon rotation of the gear21, the lifting elements 45 and 49 being in the collapsed position illustrated in Figure' 1 of the drawing, the lower or tubular lifting element 49 will be raised through the gear by the co-operation of the threads 57 and 51, provided rotation of the tubular element is prevented.

To preventsuch rotation I have provided a friction pad or shoe 65, which is pressed, by means ofa spring 71, against the outer surfa'ce of the tube. Theshoe and spring are arranged in a housing 67Y formed in the upper walls of the sleeve 13 and providing la radial duct or channel 69 the inner end Vof which opens into the channel 37. The outer end of the channel or duct 69 Vis internally threaded to receive a retaining plug 73 for the .fpurpose of securing the spring and the slice in biplace. The :housing 69 is'formed in the sleeve 13 immediately below the short end of the bearing support, that is to say, the end which is formed to the sleeve 13 in the upper end thereof, and is formed integral with the end of the bearing support soothat the housing itself is hidden out of the way below the bearing support, and further-is strengthened by the, contiguous and integral web which forms the bearing support. The plug is provided witha -sl'o't 7 5 across its outer surf-ace vwhereby its relative position in the vchannel 69 may be adjusted by means of a screw driver or'sii'nilar instrument in order to adjust the tension ofthe spring 71 and hence the force of the frictional engagement between the shoe and the tube.

l Operation Upon 'rotation of itl-re 'g`ear'2`1, the tube 49fi's projected v from lf'zollap'sed position within the sleeve by the operation of the threads 51 and 57, frictio'na'l engagement of the shoe upon the 'outer surface `of the tube preventing the rotation of the latter. Whenfthe tube reaches the position illustrated in Figure 2 of the drawing, the peg 55 lengages the .lower edge ofithegear and kprovides a positive driving connection whereby the gear rotates the tube in spite of the fricti'onal resistance of the shoe 67. Upon 'rotation of thetube, Ya lo'a'd being supported upon the head 63 and preventin itsl rotation, the shaft '45 is projected upwar vly through the tube "by lthe operation of the threads'47 Aand 53 until the fully extended jack position, illustrated in dotted lines in Figure 2, is reached. vReversing the rotation of the `gear 21 results in a likere-v versal of the lifting movements described, that is to say, the llowerjor tubular portion 49 'is retracted into thesle'eve until the peg 59 engages Pvthe upperend of the gear hub '23, the'shoe in I'the 'meanwhile preventingthe rotation of-the`slee`ve- When the sleeve'i's fully retracted, it 'is rotated by the engagement; of the gear `21"wi'th"the peg 559 which provides a positive driving connection overcoming-the frction'al resistance "olfere'd by the 'shoe 65. Further rotation results in the retraction of the shaft 45 into the tube, ther'otaft'ion ofthe shaft being prevented by 'the load supported on the head 69. L

It will be readily seen from the 'foregoing that the gear 21 provides an operating 'membercomprising an 'internally threaded collar rotatably mounted in the 'frame and having th readed engagement with the tubular member 49. f The friction pad prevents -the'member 49 from rotating and ,allows the collar to "raise the "tube inthe frame when operatively rotated. Theipeg'sinthe tubular member function tolimit its-upward and downward motion through the collar and to Lprovide a positive driving connection between the collar -and the I'tubep whereby the latter may be rotated against the resistance of the friction pad 69 whereby the tubular member itself is constituted an operating member to lift the supplementary lifting member 45, the load carrying head of which by engaging the load operates to prevent the rotation of the member to allow the tube to perform its operating function. The peg 61 limits the relative movement of the members 45 and 49.

Having thus described my invention what I claim is new and'desire to secure by Letters Patent is:

1. n a device of the class described, a frame providing housing having an opening at the upper end of the fra-me, an externally threaded extensible member arranged in said housing for projection through the opening thereof, a driving nut journaled at the upper end of the housing and threadingly engaging the extensible member, said nut having gear teeth formed in its periphery and a support member comprising a strap of width substantially less than the diameter of said nut formed integrally with and extending from the side of the frame at a point below said opening, said strap extending outwardly of the frame and upwardly ofV said opening, a bearing formed in said strap and a driving member rotatably mounted in said bearing and having a portion extending within saidstrap and operatively engaging the toothed periphery of said nut to form a driving connection therewith, said frame having an enlarged formation therein at'the junction of said strap therewith, said formation providing a duct opening into` the housing, a spring pressed friction mea-ns arranged in said duct in position to enter the housing and to frictionally engage said extensible member whereby to provide a. rotation preventing brake for the extensible member with respect to the frame upon the actuation of said operating member, the engagement of the extensible member and the brake means being friction solely, there being no interlocking or splined connection between brake n means and driving member.

2. In a device of the class described, a frame providing a housing havingan openabove the opening for rotatingly receivin and laterally supporting said nut, a journa formed'in said strap, a driving member rotatably mounted in said bearing and having aV friction means, arranged in said duct in position to enter the housing and to frictionally engage said extensiblemember whereby to provide a rotation preventing brake `for thel extensible member with respect to the frame upon the actuation of said operating member, the engagement of the extensible member and the brake means being friction solely, there being no interlocking or splined connection between brake means and driving member.

In witness whereof, I have hereunto subscribed my name. Y

MILLARD B. LUCKER.

ing at the upper end of the frame, an externally threaded extensible member arranged in said housing for projection through the opening thereof, a driving nut journaled at the upper end of the housing and threadingly engaging the extensiblemember, said nut having gear teeth formed in its periphery and a support member comprising a strap of a width Substantially less than the diameter of said nut formed integrally with and extending from the side of the'frame at a point below said opening, said strap extending outwardly of the frame and upwardly above said opening in spaced relationship with respect to the upper end of the frame, said strap. being formed with abearing in alignment 

